/Engine/Plugins/Online/OnlineFramework/Source/Party/Public/User/SocialUser.h
bool InviteToParty ( const [FOnlinePartyTypeId](API\Plugins\OnlineSubsystem\FOnlinePartyTypeId) & PartyTypeId, const [ESocialPartyInviteMethod](API\Plugins\Party\Party\ESocialPartyInviteMethod) InviteMethod, const [FString](API\Runtime\Core\Containers\FString) & MetaData ) const